/*
 * Copyright (C) 2025 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package androidx.compose.remote.core;

import org.jspecify.annotations.NonNull;

import java.time.Clock;

/** Extends java.time.Clock to allow controlling System.nanoTime for testing. */
public abstract class RemoteClock extends Clock {
    /**
     * Return System.nanoTime, or something with similar properties such as not being affected by
     * time synchronization such as NTP.
     */
    public abstract long nanoTime();

    /**
     * Helper to get nanoTime from a Clock, to allow Clock to be passed in but use as a RemoteClock.
     * Falling back to System.nanoTime.
     */
    public static long nanoTime(@NonNull Clock clock) {
        if (clock instanceof RemoteClock) {
            return ((RemoteClock) clock).nanoTime();
        } else {
            return System.nanoTime();
        }
    }
}
